James t



J. T. HALL.

BRAKE SHOE. j

.No. 511,298. Patented Dec. 19, 1893.

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UNITED FTATESM ATENT FFICE JAMES T. HALL, OF SAN FRANCISCO, CALIFORNIA,ASSIGNOR OF ONE-HALF TO LEE D. CRAIG,

B RA K E SPECIFICATION forming part of Letters Patent No. 511,298.,dated December 19, 1893.

Application filed August 2,

To all whom it may concern:

Be it known that I, JAMES THOMAS HALL, a citizen of the United States,residing in the city and county of San Francisco and State ofCalifornia, have invented certain new and useful Improvements inBrake-Blocks; and I do hereby declare the following to be a full, clear,and exact description of said invention,

such as willenable others skilled in the art to which it most nearlyappertains to make, use, and practice the same.

My invention relates to the wooden block or face piece of a brake whichcomes in contact with the surface against which the brake is applied,and althoughmy improvement can be used on all kinds and classes ofbrakes it is especially adapted for car lines'where' the brake isapplied against the upper face of the track or rail.

My invention consists first, in applying the wood which constitutes theshoe of the brake with its grain, at right angles to the surface againstwhich it is applied, so that the end of the grain will form the frictionsurface; secondly, in making holes or grooves in or across the face ofthe shoe or block; and thirdly, in filling a peculiar composition intothe holes or grooves, all as hereinafter more fully described.

Referring to the accompanying drawings, Figure l is a side elevation ofthe lower part of street car, showing track shoe in position. Fig. 2 isa detail front elevation of improved shoe partly broken. Fig. 3 is adetail of same, bottom plan. Fig. 4 is a detail of same, sectional endelevation through a: no on Fig. 2.

A represents a wooden brake block or shoe, such as is used for applyingfriction to the rail of a railway track for arresting or stopping thespeed of a car or train. 7

My invention contemplates the application to the surface of this shoe orbrake of adhesive substance that will cause the shoe or brake to adhereto or bite upon the rail with greater friction than can be obtained fromthe ordinary surface of the shoe or brake. This can be done in severalways, but I prefer to bore holes I). b. b. in the face of the OF SAMEPLACE.

SHOE.

sees] no. 482,200. on model.)

shoe or brake to the required depth and to fill the holes with africtional substance or composition that will either melt at a lowtemperature or be worn elf and rubbed into the face of the shoe or brakeby the friction due to the application of the shoe or brake to the railor other opposing surface.

. The frictional compound which I use consists of resin fifteen (15) percent. and pitch five (5) per cent, mixed with eighty (80) per cent. ofsharp quartz sand. These ingredients I mix together under heat, andwhile it is hot I pour it into the holes or grooves in the face of thebrake shoe or. block, so that when it cools it forms a part of the faceof the shoe.

, Instead of holes dovetail grooves might be provided at intervalsacross the face of the shoe or brake, into which the substance orcomposition is poured and molded.

' A shoe or brake thus constructed will yield a maximum amount offriction. The friction and wear due tothe application of the shoe orbrake against the opposing surface will cause this adhesive substance orcompound to be worn off as fast as the surface of the brake or shoe isworn and the sharp grains of sand to be rubbed and embedded into thefrictional surface between the soft and hard grain of the wood, so as tobe incorporated with it, thus preparing theentire surface of the shoe orbrake and keeping it in a condi: tion to create the greatest amount offriction.

The shoe might be prepared by immersion or saturation before use, so asto thoroughly impregnate it with the adhesive or frictional the surfaceof a rail, even if it is damp or wet.

Having thus described my invention, what resin, pitch and sharp sand,substantially as *3. Africtional composition for brake shoes,

described. consisting of resin, pitch andsharp sand, in

2. A brake block or shoe having its grain about the proportionspecified. at right angles to the braking surface and JAMES 'l. HALL. 5having holes or grooves in its face filled with \Vitnesses:

a compound of resin, pitch and sharp sand, CHAS. J. ARMBRUSTER,

substantially as described. A. S. FARE.

